Breaking changes are changes in either the .NET Framework (runtime breaking changes) or Visual Studio (design/compile/project upgrade) that make certain application and development scenarios behave differently from the version 1.0 and 1.1 .NET Frameworks to the 2.0 version.Breaking changes were made for a number of reasons, including standards compliance, customer feedback, and correctness. Follow this link to review design-time and run-time breaking changes.